Download Casting Light Upon the Waters PDF

TitleCasting Light Upon the Waters
File Size4.0 MB
Total Pages103
Document Text Contents
Page 1


Page 2

>: :<
!! ~lt-..~\\\\~ :<

\l~l\\ \
~~~" 'i. :<

!! !<

Casting tight Upon the Waters:
A Joint Fishery Assessment of the Wisconsin Ceded Territory

U.S. Department of the Interior. 1991.
Bureau of Indian Affairs, Minneapolis, MN. I 02 pp.

Second Edition, January, 1993.

Page 51

Largemouth bass fry have strong schooling
tendencies and even the adults will congregate in
small groups along the edges of weed beds in shallow
water. During daytime, they are usually in 3 to 9 feet
of water, often hiding under lily pads or in the shade
of overhanging trees. In the evening, largemouth bass
move into shallow water to feed. After dark, they
return to deep water to rest on or near the bottom.
Adult bass move into deep water and are relatively
inactive during the winter. In the spring, they migrate
into bays where the water is warmer. Largemouth
bass are compatible with most warmwater species of
fish. However, their abundance often declined when
walleye were introduced into their habitat. When both
largemouth and smallmouth bass are present in the
same waters, the two species usually occupy different
niches in the habitat but largemouth bass will often
dominate. Carp can depress populations of bass by

altering the habitat. They stir up the bottom, increase
turbidity, and uproot the weed beds that bass require ..

Natural mortality rates of largemouth bass are •
low (5.2 percent at Ridge Lake and 12 percent at Brown ·
Lake) for age two and older fish. Angling harvests,
however, present a different picture. In Ridge Lake, 23
to 40 percent of the catchable stock was harvested each '
year. In Brown Lake, anglers harvested four pounds of ,
bass per acre in 1953; about 12 percent of the total i
catchable stock. ·


The standing crop of largemouth bass in Brown !
Lake, a bass-bluegill lake in southern Wisconsin, :
averagedbetween27and33poundsperacre. Standing ,
crops of about thirty pounds per acre are considered j
normal for the glacial lakes in Wisconsin. '


Smallmouth Bass
Smallmouth bassaremembersofthesunfishfamily;

their native range is limited to the North American
continent. In Wisconsin, Greene (1935) was unable to
determine their original range because they were so
widely distributed during the cream can/ railcar era of
the late 1800's and early 1900's. However, the presence
of smallmouth bass above waterfalls in localities where
they were never stocked indicates that they probably
dispersed over most of Wisconsin during the early
post glacial period (Fig. 6). Smallmouth bass prefer
moderate to large rivers but they also do well in lakes
that have gravel bottom areas. Currently, they are
found in 214 streams (total3,514 miles) throughout the
state and in numerous lakes in the watersheds of those
streams. The southwestern comer of Wisconsin and
the Green Bay /Fox River area support the highest
abundances of smallmouth bass outside of the ceded
territory. Smallmouthareabundantin the central part
of the ceded territory of Wisconsin. The Wisconsin
Department of Natural Resources assessed the
populations of smallmouth bass in 13 lakes located
within the ceded territory. Populations (number per
acre of water) varied from a low of 0.30 in Lac Courte
Oreilles Lake (Sawyer County), to a high of 14.95 in
Nebish Lake (Vilas County), and averaged 3.01
catchable smallmouth bass per acre overall. Nebish
Lake was the onlyonewitha population that exceeded
10 fish per acre. Clear Lake in Oneida County has the
second highest population at 4.50 fish per acre.

Smallmouth bass thrive in slow to moderately
swift rivers but moving water is not essential. They
prefer warm, clear, well-oxygenated water over rocky '
or gravel bottoms. Smallmouth bass require shallow i
water areas, rocky ledges, patches of vegetation along :
the shorelines, and some relatively deep water areas in 1
their habitat. They prefer water that is slightly turbid,
moderately productive, and in the 70 to 80 F
temperature range. Dissolved oxygen levels below 1.0
ppm are lethal. At 50 F and below, smallmouth bass :
become lethargic and do not feed.

Spawning occurs from mid-May through late June ·
when water temperatures are in the 55 to 70 F range.
As spawning approaches, the males select sites and '
construct nests. Nest building occurs in the early
morning. Males assume a vertical position in the


water and sweep the bottom vigorously with their i
tails. This clears the mud, sand, and small stones from :
an area about twice the length of the fish. The male ;
waits for a female to arrive and attempts to nudge and :
push her into the nest. In the spawning act, the male
and female tum on their sides and expel eggs and milt
simultaneously. Individualspawningactsoccurevery
few minutes and it may take from two to three hours .

Page 50 Casting Light Upon the Waters

Page 52

Fl9ure 6. Original geographic range of the smallmouth bass in
Wisconsin. Map from Fishes of Wisconsin, Becker (1983).

for a female to expel all of her eggs. The eggs are sticky
and adhere to rocks in the nest. After the female
deposits 2,000 to 10,000 eggs (depending on the size of
the fish), she will leave the nest. Usually the male will
follow her for a short distance but then return to care for
the eggs. Some males are able to coax more than one
female into the nest and some females may spawn in
more than one nest before they are spent. Incubation
times range from 3 days at 75 F to 10 days at 55 F.
Smallmouth bass nests contain up to 10,000 eggs and
usually 2,000 to 3,000 fry hatch and emerge.
Smallmouth bass mortality is high during the first few
days after the fry leave the nest. Natural mortality
eliminated most of the young fish in a population before
they reached ten inches in length.

rise up out of the nest as a tight black school6 to 15 days
after hatching. The male stays with the brood for 2 to 9
days but abandons them as the school of fry begins to
disperse. Nurseryareasforsmallmouthbassaregenerally
in shallow weedy beds along the shoreline. As soon as
the fry absorb their yolk material (0.5 to 0.7 inches long),
they begin to feed on small zooplankton Reproductive
success is affected by a number of factors including: 1)
favorable temperatures during the spawning and post
spawning periods; 2) lack of flooding and high winds
during the nesting stage (severe wave action will destroy
nests); and 3) the presence of structures (logs, brush, large
rocks) in their nesting areas.

Growthratesofsmallmouth bassin Wisconsin waters
vary greatly. In southern Wisconsin (Grant, Richard, and

Lafayette Counties), young-of-the-year averaged 1.0
inches in June, 2.0 inches in July, and 28 inches in
September. Smallmouth bassaverage3 to 4inchesatage
one,6 to 7 inchesatagetwo,8 to 9 inchesatagethree,and
10plusinchesatagefour. Mostsmallmouthbass do not
survive past age 5, but a few reach 8 to 11 years of age, 18
to 20 inches in total length, and weigh 6 to 9 pounds. The
ages at maturity for smallmouth bass are: males 3 to 5
years and a size range of 8 to 12 inches; and females 4 to
7 years and a size range of 9 to 13 inches.

Smallmouth bass fry begin to feed on zooplankton
soonaftertheyleavethenest. Smallinsectsandsmallfish
have been found in the stomachs of 1.8 inch bass and
small crayfish and fish in the stomachs of 3.1 inch
smallmouth bass. Fish species consumed were: perch,
sunfish, minnows, darters, sculpins, suckers, catfish,
sticklebacks, and other bass. In Oear Lake (Oneida
County), smallmouth bass had mostly crayfish in their
stomachs, whereas, in the Plover River (Portage County)
they consumed mostly fish. Insects made up small parts
of the diets in both areas. Adult smallmouth bass spend
their daylight hours in deep pools, under river banks, or
around logs and stumps. At dusk, they become active
and move into their feeding areas. At night, they rest on
the bottom until dawn when they move into shallow
water in search of food. They feed aggressively, often
out of the water. During the winter, smallmouth bass
move into deep water and become semi-dormant. In the
summer, river bass take shelter in the lee of rocks, in
cavities under objects, or along ledges. They seem to
avoid living in beds of submerged vegetation but utilize
them as feeding grounds.

Smallmouth bass are tolerant of most other river and
lake species. However, when both smallmouth and
largemouth bass are present in the same waters, they
select different niches in the habitat. In livingston Branch
Uowa County), the standing crop of smallmouth bass
was very high (280 to 450 lbs/ acre). In the Red Cedar
River (Dunn County) and in the Plover River (Portage
County),standingcrops were in the SO to 110 lbs per acre

Female smallmouth bass cannot be stripped of their
ponds. Majorconcernsinsmallmouthbassmanagementare
habitat protection and pollution abatement. Habitat
degradation caused by lake shore development, riverine
hydropower plant construction, and increased pollution
byindustrialdevelopmenthaveadversely affected some
of the state's prime smallmouth bass waters. However,
the fish continue to thrive in northern Wisconsin with a
minimum amount of stocking.

Casting Light Upon the Waters Page 51

Page 102

Appendix 1

Joint Assessment Steering
Committee Budget Summary

Great Lakes Indian Fish and Wildlife Commission

Steering Committee Expenses ........................................................... $17,000

Report Publication Cost ...................................................................... $25,000

Expanded G.L.I.F.W.C. Fishery Assessment ................................... $134,900





St. Croix Fishery Assessment Unit ..................................................... $33, 100

U.S. Fish and Wildlife Service

Data Collection; Report Preparation/Editing/Meeting Facilities .......... $66,000

Travel ................................................................................................... $8,000

Equipment/Supplies ........................................................................... $16,000

Casting Light Upon the Waters Page 101

Page 103

















Similer Documents